# import random
# import requests
#
# def find():
#     li = ['陈'] * 10000 * 1000
#     ran_num = random.randint(0, len(li)-1)
#     li[ran_num] = '钦'
#     num = li.index("钦")
#     print(num)
#     # print(li)
# find()
#
#
# r = requests.get("https://www.baidu.com/")
# print(r.content.decode("utf-8"))

# a = 999
# b = 999
# print(id(a), id(b))
# print(a == b)
# print(a is b)

# f = open('a.txt')
# lines = f.read()
# print(lines)
# f.close()

# f = open('a.txt')
# lines = f.readline()
# print(lines)
# print(type(lines))
# f.close()

f = open('a.txt')
lines = f.readlines()
it = iter(lines)
print(next(it))
print(next(it))
print(next(it))
# for line in lines:
#     print(line)
print(type(lines))
f.close()

# f = open('a.txt')
# lines = f.readlines()
# it = iter(lines)
# print(next(it))
# print(next(it))
# print(next(it))
# # for line in lines:
# #     print(line)
# print(type(lines))
# f.close()

ll = range(10)
print(type(ll))
ll = iter(ll)
print(type(ll))
print(next(ll))

l = ['test']
print(','.join(l))